Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A75103

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N57016 · BOEING 777-200 · operated by UNITED AIRLINES INC

Hex
A75103
Octal
51650403
Decimal
10,965,251
Country
US
Tail
N57016
Type
B772
No current signal · last broadcast 2h ago
Flights observed
222
Distinct callsigns
20
Country
US
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S A75103.

Country allocation

The ICAO 24-bit address A75103 falls within the block assigned to United States (US) by ICAO Annex 10, Volume III. Every aircraft registered in United States receives a permanent address from this block at the time of registration; the address stays with the airframe even if the aircraft is re-registered to a different operator within the country.

Callsign history 20 distinct

Callsign Airline Flights Last seen
UAL933 - 13 2026-07-05
UAL927 - 13 2026-07-09
UAL876 - 11 2026-06-30
UAL926 - 9 2026-07-09
UAL506 - 8 2026-07-13
UAL131 - 8 2026-06-29
UAL932 - 7 2026-06-20
UAL889 - 7 2026-07-12
UAL888 - 7 2026-07-11
UAL875 - 7 2026-06-13
UAL917 - 5 2026-07-10
UAL916 - 5 2026-07-11
UAL901 United Airlines 5 2026-04-24
UAL900 United Airlines 5 2026-04-17
UAL45 United Airlines 5 2026-06-23
UAL44 United Airlines 5 2026-06-22
UAL130 United Airlines 5 2026-05-23
UAL96 United Airlines 4 2026-06-01
UAL924 - 4 2026-07-06
UAL837 United Airlines 4 2026-04-23

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-13 UAL506 - Jul 13, 14:35 UTCJul 13, 17:15 UTC2h 40m
2026-07-13 UAL506 FCO → SFO Jul 13, 14:07 UTCJul 14, 02:43 UTC12h 36m
2026-07-13 UAL507 - Jul 13, 00:25 UTCJul 13, 11:25 UTC11h 0m
2026-07-12 UAL889 - Jul 12, 10:40 UTCJul 12, 12:40 UTC2h 0m
2026-07-12 UAL889 PEK → SFO Jul 12, 09:51 UTCJul 12, 20:56 UTC11h 5m
2026-07-11 UAL888 - Jul 11, 18:15 UTCJul 12, 05:50 UTC11h 35m
2026-07-11 UAL916 - Jul 11, 02:05 UTCJul 11, 13:30 UTC11h 25m
2026-07-10 UAL917 SFO → AKL Jul 10, 06:46 UTCJul 10, 19:11 UTC12h 25m
2026-07-10 UAL917 - Jul 10, 06:50 UTCJul 10, 07:20 UTC30m
2026-07-09 UAL927 - Jul 9, 16:10 UTCJul 9, 18:45 UTC2h 35m
2026-07-09 UAL927 FRA → SFO Jul 9, 15:51 UTCJul 10, 02:58 UTC11h 7m
2026-07-09 UAL927 FRA → SFO Jul 9, 15:51 UTCJul 10, 03:03 UTC11h 12m
2026-07-09 UAL926 SFO → FRA Jul 9, 03:35 UTCJul 9, 13:45 UTC10h 10m
2026-07-08 UAL195 - Jul 8, 14:00 UTCJul 9, 01:20 UTC11h 20m
2026-07-08 UAL102 - Jul 8, 02:05 UTCJul 8, 11:55 UTC9h 50m
2026-07-08 UAL102 IAH → MUC Jul 8, 00:52 UTCJul 8, 11:53 UTC11h 1m
2026-07-06 UAL4 - Jul 6, 15:15 UTCJul 7, 00:40 UTC9h 25m
2026-07-06 UAL924 IAD → LHR Jul 6, 04:55 UTCJul 6, 11:25 UTC6h 30m
2026-07-05 UAL933 FRA → IAD Jul 5, 16:15 UTCJul 6, 01:10 UTC8h 55m
2026-07-05 UAL933 FRA → IAD Jul 5, 15:46 UTCJul 6, 01:10 UTC9h 24m
2026-07-05 UAL926 SFO → FRA Jul 5, 02:45 UTCJul 5, 13:05 UTC10h 20m
2026-07-02 UAL673 - Jul 2, 14:55 UTCJul 3, 02:30 UTC11h 35m
2026-07-02 UAL672 SFO → BCN Jul 2, 01:20 UTCJul 2, 11:55 UTC10h 35m
2026-07-01 UAL59 - Jul 1, 11:30 UTCJul 1, 13:20 UTC1h 50m
2026-07-01 UAL59 FRA → SFO Jul 1, 11:29 UTCJul 1, 22:16 UTC10h 47m
2026-07-01 UAL59 FRA → SFO Jul 1, 11:29 UTCJul 1, 22:03 UTC10h 34m
2026-06-30 UAL58 SFO → FRA Jun 30, 21:30 UTCJul 1, 07:25 UTC9h 55m
2026-06-30 UAL876 HND → SFO Jun 30, 07:15 UTCJun 30, 15:56 UTC8h 41m
2026-06-30 UAL876 - Jun 30, 07:20 UTCJun 30, 07:55 UTC35m
2026-06-29 UAL131 EWR → HND Jun 29, 15:53 UTCJun 30, 04:44 UTC12h 51m
2026-06-29 UAL131 - Jun 29, 15:54 UTCJun 30, 04:45 UTC12h 51m
2026-06-29 UAL1141 SFO → EWR Jun 29, 05:54 UTCJun 29, 10:29 UTC4h 35m
2026-06-28 UAL889 PEK → SFO Jun 28, 10:30 UTCJun 28, 12:09 UTC1h 40m
2026-06-28 UAL889 PEK → SFO Jun 28, 09:51 UTCJun 28, 20:18 UTC10h 27m
2026-06-27 UAL888 SFO → PEK Jun 27, 18:15 UTCJun 28, 07:12 UTC12h 57m
2026-06-27 UAL888 SFO → PEK Jun 27, 18:15 UTCJun 28, 06:10 UTC11h 55m
2026-06-27 UAL916 AKL → SFO Jun 27, 02:09 UTCJun 27, 13:55 UTC11h 45m
2026-06-27 UAL916 AKL → SFO Jun 27, 02:11 UTCJun 27, 13:50 UTC11h 39m
2026-06-26 UAL917 SFO → AKL Jun 26, 07:14 UTCJun 26, 19:30 UTC12h 15m
2026-06-24 UAL927 - Jun 24, 16:05 UTCJun 24, 17:50 UTC1h 45m
2026-06-24 UAL927 FRA → SFO Jun 24, 15:51 UTCJun 25, 02:48 UTC10h 57m
2026-06-24 UAL926 SFO → FRA Jun 24, 02:45 UTCJun 24, 13:00 UTC10h 15m
2026-06-23 UAL45 ZRH → SFO Jun 23, 12:15 UTCJun 23, 23:29 UTC11h 15m
2026-06-22 UAL44 SFO → ZRH Jun 22, 21:48 UTCJun 23, 08:20 UTC10h 32m
2026-06-22 UAL44 SFO → ZRH Jun 22, 21:54 UTCJun 23, 08:25 UTC10h 30m
2026-06-21 UAL949 - Jun 21, 12:40 UTCJun 21, 23:14 UTC10h 35m
2026-06-21 UAL924 IAD → LHR Jun 21, 02:50 UTCJun 21, 09:24 UTC6h 35m
2026-06-20 UAL933 FRA → IAD Jun 20, 16:05 UTCJun 21, 00:14 UTC8h 10m
2026-06-20 UAL932 - Jun 20, 02:54 UTCJun 20, 09:49 UTC6h 55m
2026-06-19 UAL933 FRA → IAD Jun 19, 15:34 UTCJun 19, 23:54 UTC8h 20m

About Mode-S

A Mode-S transponder code (also called an "ICAO 24-bit address" or "hex code") is a 6-character hexadecimal identifier permanently assigned to an aircraft when it's first registered. Unlike callsigns (which change with each flight) or registrations (which can change if an aircraft is sold internationally), the Mode-S address stays with the airframe for the life of the aircraft in that country.

Every ADS-B transmission from an aircraft includes its Mode-S address, making it the most reliable way to identify a specific airframe. Flight-tracking services like Apparatus use the Mode-S address as the primary key for tying position broadcasts, callsigns, and ownership records together.

Prefer a tail-number view? See the N57016 page for operator, model, and routing details .

Mode-S A75103 frequently asked

What is Mode-S code A75103?
A75103 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N57016.
Where is Mode-S A75103 registered?
Mode-S code A75103 is allocated to United States (US). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is A75103 broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A75103, octal 51650403, decimal 10,965,251.
What flights does A75103 operate?
Mode-S A75103 has broadcast 20 distinct callsigns, including UAL933, UAL927, UAL876, UAL926, UAL506.